Fluid-pressure signal-valve



No. 620,6m. `Patented Mar. 7, |899.

H. n. MASON. FLUID PRESSURE SIGNAL VALVE.

(Application led June 17, 1898.)

2 Sheets-Sheet I.

(No Model.)

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Patented Mar. .7, |899. H. R. MASON. FLUID PRESSURE SIGNAL VALVE.

2 Sheets Sheet 2.

No. 620,6ul.

(No Model.)

llillllillllll Y 7%@ M l MNTIAMMNM /\\|i\ lll/ily" Humm UNITED STATESPATENT OFFICE.

HARRY R. MASON, OF CHICAGO, ILLINOIS.

SPECIFICATION forming part of Letters Patent No. 620,601, dated March 7,1899.

Applicatin filed June 17, 1898. Serial No. 683,682. (No model.)

To @ZZ whom it nca/ zj concern,.-

Be it known that I, HARRY R. MAsoN, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a new and useful Improvement in Fluid-Pressure Signal-Valves,of which the following is a specification. a The signal-valve to whichmy invention relates forms part of a fluid-pressure signaling systemparticularly adapted for use upon railway-trains.

Broadly stated, the system involves a signalin g or train pipe which iskept charged with air under pressure from the main reservoir of theair-brake system, conductors signalingvalves on cars of the train, and asignal-valve device on the locomotive. .The signaling is performed byoperating a conductors signaling-valve to produce the escape of alimited quantity of air, and thus generate a negative or signalingimpulse which travels through the signaling-pipe to the signal-valve,causing the latter to vent air to a signal, preferably a whistle.

My present invention relates particularly to a signal-valve of thenon-interference type and is in the nature of an improvement upon theconstruction shown, described, and claimed in Letters Patent No.534,401, granted to me February 19, 1895. The said patented valve wasconstructed to operate upon trains of any length and, while sounding thewhistle once under each direct impulse generated at a conductorssignalingvalve, prevent the undue repetition of signals under thefluctuations of pressure in the signaling-pipe following upon the directimpulse.

My object is to improve upon the said patented construction for thepurpose of rendering the signal-valve more sensitive to operation undersignaling impulses and for hastening the replenishment'of thesignaling-reser-l voir under rise of signaling-pipe pressure, so thatthe signals may be produced in more rapid succession. a a

` In the drawings, Figure l is a vertical section of a valve deviceembodying my improvements in their preferred form; Fig. 2, a verticalcentral section of the valve device of modified form, the section beingat a right angle to the section shown in Fig. l; and Fig. 3, a brokensection of that part of the valve shown in Fig. 2 which connects withthe signaling or train pipe.

The valve device A is formed, preferably, in two sections A A2, with agasket between them. In the shell formed by the sections is a chamber s,communicating near its top through a cored passage fr with the signalingor train pipe at B. Communicating with the passage r is a port orpassage r', on which is mounted the usual train-pipe pressure-gage. (Notshown.) In the center of the lower part of the chamber s is a verticaltube or sleeve s', formed toward its lower end wit-h a valve-seat s2,surrounding a port q, leading to a cored passage q, which extends to thesignal or whistle C. Partly surrounding that portion of the shell inwhich the tube s is mounted is a port p, communicating with a passagep', which Vin practice leads to the signaling-reservoir.

(Not shown.) In the upper part of the chamber s is an annular bushings3. Fitting closely against the said bushing and Working therein is amovable abutment or piston fn, which in the preferred construction hasan opening through its center surrounded by a valve-seat fa', adownward-extending tube n2 around said opening, and aninternally-threaded sleeve n3 above said opening. The tube or stem n2fits and slides in the stationary tube s. Screwed into the sleeve n3 isa cap or plug piece n4, forming in its under side a valvechamber 715,communicating with the chamber s through ports n. In the upper part ofthe-plug-piece or cap n4 is a horizontal openingr', elongated in thevertical direction. In the tubular stem nzis awinged pinm, formed at itslower end to produce a valve ivi/,which seats upon the seat s2 to closethe port q, and formed toward its upper end with a valve m2, which seatsnormally upon the valve-seat n. Above the valve m2 the pin is providedwith an upward-projecting part ma, which terminates normally a shortdistance below the surface of a stop u8 in the plug or cap piece n4.Surrounding the parts m3 fn-S is a confined spring m4, which tendsnormally to press the valve m2 to the seat n. In the side of the tubes', near the lower end thereof, is a port s,

It will be seen that the main difference between the presentconstruction and the aforesaid -patented construction lies in this thatthe piston n lits closely against the bushing loo ' as that ofthesignaling train-pipe.

83, inV a manner, however, to slide readily therein, and that thepassage for air from the signalingpipe to the signalingreservoir isthrough the ports n, tube n2, and port s4 when the valve m2 is open. Thepiston is shown in its normal position,which is the one it will occupywhen pressure on opposite sides is substantially balanced. When thepressure above the piston from the train-pipe eX- ceeds the pressurebelow the piston from the signaling-reservoir, the piston will bepressed downward against the resistance of the spring mi to move theseat n downward from the valve m2, thus opening the latter andpermitting air to pass quickly from the train-pipe to thesignaling-reservoir. When the pressures on opposite sides of the pistonare substantially equalized, the spring 'm4 will raise the piston to thebalanced or normal position shown. The pin m is held in the position ofclosing the port q by the relative suction action at the port q. l

Above the chamber s and in open communication therewith is a chamber Z,provided with an annular bushing Z. Working in the chamber Z isa piston7c, provided on its under side with a downward-extending lug Zc,carrying a pin k2, which extends through the slot or opening nl of thepiston-cap. The piston lo fits loosely in the bushing Z to permit air topass between the chambers s Z around the edge of thc pistou. Astop-plate k3 is fastened bya screw in the top of the chambers, asshown, and projects across the piston Zo to limit the movement of thelatterin the downward direction.

On the shell-section A is a chamber z', closed at the top by a screw-capfi. A cored passage 2 extends to the chamber z' from the passage 1.Between the chambers Z and 'Z Vis a vent-passage i5, formed at its topin the chamber i with a valve-seat 4 for a check-valve i5, which mayrise to a stop 6 to open said passage.

In operation the train-pipe air enters the chamber i' and the top of thechamber s, whence it passes around the piston lo into the top of thechamber Z. As the pressure rises in degree above the piston n it pressesthe pin m to its seat upon the port q and presses the piston n downwardagainst the resistance of the spring m4 to open the valve m2, wherebythe air passes to the under side of the piston in the chamber s andthence through the port p to the signaling-reservoir until the latter ischarged to approximately the same pressure The conductorssignaling-valves which I employ operate when actuated to vent a certainpredetermined volume or degree of pressure, whereby each direct impulseis initially the same. As explained by me in previous applications andnow thoroughly understood in the art, a signaling impulse generated ataconductors signaling-valve in a long train is necessarily weaker whenit reaches the signaling-valve than it would be in a short train and theforce of fluctuations is greater in a short train-pipe than in a longone. The means I providein the present construction to prevent theoperation of the signal under the iiuctuations of pressure are, it willbe seen, substantially the same as the means shown in my aforesaidpatent. Each time a signaling impulse is generated at a conductorssignaling-valve it travels to the signal-valve A and momentarily lowersthe pressure in the chamber s above the piston, causing the superiorpressure in the signaling-reservoir to raise the piston, open the valvem', and permit air from the reservoir to pass through the port q andsound the whistle. "When the signaling impulse, as in a long train, iscomparatively weak, it will raise the piston until the lower edge of theopening a7 strikes the pin k2, after which it will descend again toclose the port q. When the signaling impulse is strong, as in a shorttrain, the piston will be raised and raise the return-retardingmechanism or piston k, forcing the air from the chamber Z to the chamberi', and cause comparatively slow return of the valve m to its seat,owing to the drag thereon produced by the piston lc, all as explained inmy aforesaid Letters Patent. The result of this operation is that inevery case a somewhat prolonged and decided blast will be given to thewhistle. soon as the piston n is lowered by the predominating pressurefrom the train-pipe and the valve m is closed the piston under any riseIOO of train-pipe pressure will be moved still farther downward againstthe resistance of the spring m4, thereby opening the comparatively largepassage through n@ n' n2 s4, whereby the signaling-reservoir is chargedvery quickly approximately up to the train-pipe pressure. In practicethis recharging will take place in less than a seconds time, while in myformer construction the recharging took a materially longer time.Furthermore, as in the present construction the passage between oppositesides of the piston is normally closed instead of, as in my formerconstruction, open, the piston is rendered more sensitive, which I findin practice to be a decided advantage.

In the modified construction the piston n fits the bushing s3 as tightlyas practicable, and instead of the' tubular extension n2 and pin m Iprovide the solid stem Zt, formed at its lower end with a valve m toopen and close the port q. On the side of the shell-section A2 isacheck-valve device A3, comprising a chamber f, communicating at itslower side through a cored passage f with the trainpipe passage r andcommunicating toward its upper side through a cored passage f2 with thechamber s below the piston n. In the chamber f is a check-valve f3,seating in the direction of the train-pipe. In other respects the valvedevice is like the preferred construction shown in Fig. 1.

The operation of the valve of the modified form is in every respectV thesame as that of the preferred form, except that the lower part IIO ofthe chamber s and the signaling-reservoir are charged through thepassage f ff'2 and retrogression of pressure from the reservoir to thetrain-pipe is prevented by the checkvalve f3.

Vhat I claim as new, and desire to secure by Letters Patent, is"

1. In a duid-pressure signaling system, the combination with asignal-valve device provided with valve mechanism interposed between asignaling-pipe and a signaling-reservoir, and subject on its oppositesides to pressure therefrom, respectively, and normally closing anoutlet from said reservoir to the signal, and movable from normalposition to open said outlet under pressure from the said reservoir whenthe train-pipe pressure falls under a signaling impulse, and havingreturnretarding mechanism for the said valve mechanism following theaction of the reservoirpressure to afford yieldingresistance to thereturn of the valve mechanism to normal position under predominatingpressure in the signaling-pipe following said impulse, of lacharging-passage through which the uid passes from the signaling-pipe tothe signaling-reservoir, and check-valve mechanism in saidcharging-passage for preventing retrogression of fluid from thesignaling-reservoir to the signaling-pipe, substantially as and for thepurpose set forth.

2. In a Huid-pressure signaling system, the combination with a valvedevice provided with a chamber, a piston fitting closely the Wall ofsaid chamber and interposed between a signaling-pipe and asignaling-reservoir and subject on opposite sides to pressure therefrom,respectively, and normally closing an outlet from the said reservoir tothe signal, and movable from normal position to rise and open saidoutlet under pressure from the said reservoir when train-pipe pressurefalls under a signaling impulse, and having returnretarding mechanismfor the said piston following the action of the reservoir-pressure toaord yielding resistance to the return of the piston to normal positionunder predominating pressure in the signaling-pipe following saidimpulse, of a charging-passage forming the communication between thesignalingpipe and signaling-reservoir for charging the latter, andcheck-valve mechanism in said charging-passage for preventingretrogression of fiuid from the signaling-reservoir to thesignaling-pipe, substantially as and for the purpose set forth.

3. In a fluid-pressure signaling system, a signal-valve device having achamber communicating at its upper side With the signaling-pipe, at itslower side with the signalingreservoir and through an outlet-port at itslower side with the signal, a piston in the chamber exposed at oppositesides, respectively, to pressure from the signaling-pipe and signalingreservoir, return retarding mechanism for the piston following theaction of the reservoir-pressure to aord yielding resistance to thereturn of the piston to normal position under predominating pressure inthe signaling-pipe following a signaling impulse, a reservoir-chargingpassage through the piston, and a stem provided with a valve to seatupon said outlet-port, and a check-valve at said charging-passage, allarranged to operate substantially as and for the purpose set forth.

HARRY R. MASON.

Inpresence of- M. J. FROST, R. T. SPENCER.

